A balloon recovered off the coast of Alaska had been in the ocean for “well over a year,” the Pentagon said Friday.

The balloon was discovered floating in the ocean by commercial fisherman in late-February. The fishermen shared photos of the suspicious object with law enforcement, who were concerned it could be another Chinese spy balloon similar to the one that flew across the United States last year before it was shot down.

The origin of the balloon found off Alaska remains unclear, and the fact it had been in the water so long means it could have floated for hundreds of miles or more before it was finally found three weeks ago.

Some of the balloon debris, which had been held at Joint Base Elmendorf-Richardson, has been transferred to other facilities for further evaluation and analysis, Pentagon spokeswoman Sue Gough said in a statement.

“Some material has been transferred to U.S. government facilities for further examination and analysis,” Gough said. Gough was unable to provide more information on where the ongoing analysis would take place.

The US assessed that the spy balloon shot down last year was part of an extensive surveillance program run by the Chinese military, as CNN reported at the time. The balloon fleet, according to US officials, had conducted at least two dozen missions over at least five continents in recent years.

China appeared to suspend the program following the episode, and it’s not clear whether it has been restarted. Taiwan in January accused Beijing of flying multiple balloons through its airspace.

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